body {
    overflow: hidden;
    user-select: none;
}
svg {
    display: block;
    margin-left: auto;
    margin-right: auto;
    max-width: 90vw;
}
.logo {
    margin-top: 75px;
    text-align: center;
}
.playground {
    margin: 25px auto 75px;
    width: 760px;
}
.back {
    width: 100px;
    height: 50px;
    margin: 0 auto;
}